View Full Version : Long Question.... PLEASE HELP....Anyone!

09-13-2002, 04:40 AM
I recently changed the A/C compressor and dryer on my 90sc. Starting from that point my SC has had a major problem. I don't think the two are directly related, just wierd. Symptoms are when taking off, if the accelerator is pressed past the halfway point the engine will just bog down like there is no fuel being delived. Car will jerk and shake, like a perosn trying to drive a manual trans. for the first time. Also, while sitting still, if you press the gas all the way to the floor, RPM's will go up to about 2500 then quickly fall back to 2000, then back to 25, so on and so on. During this time the boost guage will go over to around 8lbs and just sit there. Sometimes the boost guage will quickly shoot up to 11 and then fall right back immediately to 7-8. I read the codes and it gave me these 3. Left bank and right bank too lean and MAF. I changed the MAF and still same problem. Now, there are no codes coming up. I also replaced the air filter, fuel filter, spark plugs,both cats, and mufflers. I'm still waiting on the spark plug wires to come in. While driving (any gear) car will accel. if pedal is pressed slowly or if you let off pedal to a certain point. For the most part in gears 1&2 while accel. can't go over 1-2lbs of boost. For gears 3,4,&5 can't go over 5lbs of boost. Any help or suggestions would be very appreciated. Could this be a vacuum leak or something like that? For any other info, just ask.

09-13-2002, 07:17 AM
Sounds like lack of fuel to me. Have a shop test for fuel pressure.
This reminds me of a hilarious story of my friends 86 Mustang 4 cyl we called the "grey bomb" It had a 1 barrel carb and a mechanical fuel pump on the side of the engine block.
The car would idle and drive okay normally. When you rugged it from a stop sign it would accelrate hard up to 4000 rpm, then all of a sudden it was like you turned off the key. boooooggggggggg bang bang bang pop! down to 1500 rpm then it would take off again. Once it hit 4000 rpm the carb would run dry because we were using more fuel than the filter would allow to pass. A new fuel filter fixed the problem.
In your case, it sounds like either the pump itself is faulty, or the suction screen inside the tank is plugged.

09-14-2002, 04:52 AM
Friday afternoon I drove up to my buddy's work at the local muffler/exhaust shop to change out the plug wires. Plug wires aren't too bad when you have access to lift. Anyways, after the wires were done, car still had the same problem. We started messing around with some of the vacuum lines, just looking and testing really when the car just died. It would not restart for anything. Started investigating and the fuel pump wasn't working at all. Lifted the car up and started tapping on the gas tank where the pump is and the pump kicked on for about 3 secs. It was making some awful sounds and then it died for good. I sure hope this fixes my problems. Thanks for the replys, guys.

MIKE 38sc
09-14-2002, 08:59 PM
I know exactaly what is wrong! The hot wire that is connected on the fuel pump is loose and losing contact. I will post a picture of the problem tomarrow to show you the problem. Beleive me you are going to be SHOCKED at what you see.

MIKE 38sc
09-15-2002, 01:11 PM
Well as promised here are the pictures showing the culprit of your problems. The connection on the fuel pump itself is LOOSE. Take a look at the red wire that is going to the pump. Notice how the red wire turns BLACK as it gets closer to the fuel pump. Notice also how the plastic insulator on top of the fuel pump is BURNT black as well. All of this burning takes place because the connection has loosened and is arcing inside the fuel tank and causing great amounts of heat. When I install my new fuel pump ALL internal connections will be HARDWIRED[soldered] so that I will not have this problem again.

MIKE 38sc
09-15-2002, 01:14 PM
Here is another angle.

09-15-2002, 11:00 PM
:eek: That was INSIDE the tank? Man, that scares the hell out of me. .:eek:
Has anyone else ever noticed this?

09-15-2002, 11:54 PM
Here's a question that just pops into mind:

Why hasn't this thing blown up yet? Not enough heat to ignite the fumes? Doesn't seem like it would take much. Always wondered how sticking the electric pump into the tank wasn't a death trap?

09-16-2002, 10:27 AM
Probably too many vapours inside the tank to ignite. Just like in your cylinder, the fuel:air mix has to be just right to ignite fuel.
I've had similar training with propane. If you have a propane leak in an area, there can either be too much or too little propane to have an explosion. The right amount though and look out.
Seems pretty scary though.

MIKE 38sc
09-17-2002, 02:39 PM
Yes that was INSIDE my tank, and yes it is the STOCK fuel pump. Assclown how do you mean the connector would crack and fall off? Katoom you are correct, vapor concentration to high for explosion. However there was another problem that could have caused a problem. The vent on top of the tank was NEVER connected at the factory, so I had an open vent direct to the atmosphere and under the right conditions it could have been very bad. While this certainly shocked the hell out of me it did not shock ANY mechanic I have shown this to, so it is pretty common. Every single mechanic I showed it to imediately said "Thats out of a T-bird" ! hmmmmmm.

MIKE 38sc
09-17-2002, 06:29 PM
Assclown there is no plastic connector on the fuel pump. The connection is made with a spade connector just like on a speaker. The connector had gotten so hot that the metal fatigued and relaxed causing the connector to just flop around on the terminal. The only reason it did not fall off was that the wire is very stiff and kept the connector down on the terminal.

09-17-2002, 11:57 PM
Does anyone in here think that it would be a wise idea to solder the spade. I took an extra pump out of my parts car and it looks to be fine. My 90 Coug has 275,000km and it is the original fuel pump, I've never had a problem with it to date. (Knock on wood)
I wonder if Mike 38SC runs his fuel tank at a low level frequently. If you keep your tank normally full, or in the higher ranges if it would keep the pump and electrical connections cool, therefore reducing the chance of arcing and loose connections.